UPDATE: January 14, 2015: http://luckypeach.com/on-msg-and-chinese-restaurant-syndrome/ here's another opinion much of which mirrors my own. When I posted this write-up, it caused a bit of a stir.

Chinese Restaurant Syndrome Defined

Usually blamed on ingestion of Monosodium Glutamate, a set of symptoms
including headache, joint pain, upset stomach, dizziness, sweating, and myriad
others, the most significant being difficulty breathing, that occur with less frequency.

The Facts About MSG

Used exclusively as an enhancer of food flavors, MSG does not have a
distinctive taste nor odor. It does, however, stimulate glutamate
receptors in the tongue, which enable us to taste things that are "savory."
Monosodium Glutamate is the sodium salt of glutamic acid, an amino acid.
Glutamate naturally occurs in foods rich in protein, and also in the human body.
Monosodium Glutamate is made by a process of fermentation and purified for human
consumption. Monosodium Glutamate is a crystalline white powder, distinguishable
by the naked eye at very close range by its elongated, thin crystals.

Monosodum Glutamate is a common ingredient in processed foods. It was
first sold to consumers in the U.S. as a flavor-enhancing ingredient under the label "Accent," — that
brand is still sold today. Asian chefs favor the Ajinomoto
brand of MSG, manufactured by the Japanese company of the same name.

Monosodium Glutamate is a "free" glutamate. It is rendered so by
utilizing enzymes to break down proteins which contain glutamate.
Protein-bound glutamate does not have the flavor-enhancing effect of free
glutamates. Free glutamates also occur as a result of food processing.

THE CHEMICAL FORMULA FOR MONOSODIUM GLUTAMATE:

C O O Na
|
C H2
|
C H2
|
C H — N H2
|
C O O H

UPDATE 1/31/07: OldMiner says re Chinese Restaurant Syndrome: The chemical formula you present would be understood by anyone who's taken ochem, I imagine, but as it is, it looks liked you have the topmost carbon linking to an oxygen, that oxygen to another oxygen, and then a terminal sodium. What with the electrophilia of your average oxygen, this just doesn't happen. It's more O - C - O- +Na . Similarly, the C H - N H2 is more of a H C N H2. And the terminal carbon, it's the same as with the first carbon. In fact, the last carbon is basically like the first, but the acid has lost its H in that case. There's a decent 3D depiction of the group over on Wikipedia. Or if you want a more formal picture, Chemfinder's version of the whole compound is here, but it's not in pretty 3D.

The Science (or Lack of it) Behind Chinese Restaurant Syndrome

Many scientists in government and in the private sector have researched
whether or not MSG is, in fact, an allergen. Research has also been done
on the long-term consequences of MSG ingestion at varying levels. The
overwhelming majority of studies conclude that MSG is harmless.

MSG IS HARMLESS: At a Glance

1959: The U.S. Food and Drug Administration ("FDA") classifies MSG
and "generally recognized as safe," per an amendment to the Federal Food, Drug
and Cosmetic act, which requires FDA approval of the use of food and cosmetic
additives before they may be marketed to consumers or used in consumer
products.

1970: The FDA begins to sponsor reviews substances classified as
"generally recognized as safe," to further investigate the safety of such
substances.

1980: The Federation of American Societies for Experimental Biology
(FASEB), an independent research group working on behalf of the FDA, concluded
that MSG was safe for consumption at conventional levels. The FASEB did,
however, recommend to the FDA that further investigation should be conducted
to determine the safety of consuming extremely high levels of MSG.

1986: The FDA Advisory Committee on Hypersensitivity to Food
Constituents concludes that MSG poses no threat to the general public but that
reactions of brief duration might occur in some people.

1987: MSG is placed in the safest category of food ingredients by
the Joint Expert Committee on Food Additives of the United Nations Food and
Agriculture Organization and the World Health Organization.

1991: The European Community's Scientific Committee for Foods deems
MSG safe for all populations, including premature infants.

1992: The American Medical Association's Council on Scientific
Affairs states that glutamate in any form has not been shown to be a
significant health hazard.

The Internet Website MSGTruth.org insists that MSG is harmful to humans when
consumed. Support for their hypothesis consists of only (a) the 1986 FDA
Advisory Committee mention of short-lived reactions in a small subset of the
population, and (b) the fact that two studies that deemed MSG harmless were, in
fact, paid for by manufacturers of processed foods and of MSG.

An Unscientific Look At Chinese Restaurant Syndrome

"I can't eat anything with MSG. I get deathly ill if I eat even a little."
Chinese restaurant personnel hear this from a small percentage of their clientele.

Every restaurant in the United States must, according to Federal mandate,
have at least one Qualified Food Operator (QFO) in their employ. Many
states require a backup QFO, in order to have a QFO on-premises at all times.
QFOs are educated and certified in food safety and sanitation. QFOs are well-versed in the many different
kinds of food-borne illnesses that may befall eaters in general
(not just restaurant diners).

When investigating symptomatic complaints by restaurant customers there are
many causations other than MSG to consider:

The general health of the consumer

Other foods the individual has consumed that day

Whether or not the individual has ingested beverage alcohol, and at what
time

Finally, the wholesomeness of the food from the standpoint of
proliferation of bacteria

Chinese restaurant personnel who must address customer complaints of "MSG
sickness" are well-advised to inquire about the four items listed above in the
event that MSG indeed was not used in the making of the customer's meal.

It's important to note that there is, indeed, a population sensitive to MSG. Regardless the reason, these individuals should be mentioned herein in the name of objectivity.

This writeup caused a stir with one of my sources. The following was
posted originally under E2 Nuke Request:

(thing) by Carol H (13.8 hr) (print) Thu Mar 23 2006 at 3:47:52

Please delete the following http://everything2.com/index.pl?node_id=506982
The author states incorrect information about my website MSGTruth.org and I
don't appreciate it. I have spent hours putting pages of scientific research
studies on my website and he wrongly asserts that I only back up my position
with only two studies. Please check out my website http://www.msgtruth.com and
click on Related Research. The author of the completely biased writup does not
state his background - he owns several Chinese Restaurants and so is quite a
biased source. I on the other hand have a degree in food science and have worked
in R&D for Fortune 100 companies in the US - Not car companies like the author
of the biased writeup - but actual food companies. If you want accurate info on
MSG - don't ask a restaurant owner, or a CAR salesman - ask a food scientist.
Me.

Chinese Restaurant Syndrome...Have asked the author of the writeup in
question for his thoughts and have advised this poster that many of our writeups
are subjective in nature, so on and so forth. And, well, have asked her, as
requested, to write an accurate piece on MSG for us. -TDG

I sincerely apologize to Carol H for not having perused her site more
thoroughly.

I deeply regret, however, that she glossed over my homenode in a similar
fashion. Four years of my thirty-five year business career were spent
working at Ford, in commercial fleet operations. I am not, and never have
been a "car salesman." I resent being called one, in fact. I only included
my experience at Ford (as well as IBM) to illustrate that I began my career in
the corporate world and then veered off to less conventional employment.

I am an owner of Asian themed restaurants. That's how I make my
living. I have fourteen years of experience in this specific business at
this point, and my unscientific observation is that Chinese Restaurant
Syndrome is more often caused by bad food served by unscrupulous or uneducated
proprietors rather than by MSG. Either way, Chinese Restaurant Syndrome
is giving my industry a bad name.

I did not and will never advocate giving MSG to any person who in any way
believes they have, or is diagnosed with, a sensitivity to that substance.

I am not a food scientist. I do, however, have current certification in
Food Safety from the states of New York and Connecticut (although Connecticut's
course is a one-day joke; New York's is a week of seminars and tests).

Finally, let's talk about freedom of speech and censorship. Carol H
would have anything that presents a point of view about MSG other than hers
removed from E2. Now, I've read plenty of stuff on E2 that I disagree
with. If I want to discuss, I /msg the writer, with my email, and we agree
to disagree. I invite Carol H to learn how to node and then write one that
expresses her point of view.

Let's reverse positions for a moment. If Carol H could simply sign-up and
blast my node to node heaven or worse, why then can I not contact her
web-hosting company and tell them to remove her site from the internet, because
I happen to disagree with some of its content? Why then, can I not contact
her ISP and tell them that she's disseminating information that could
potentially impact the way I make money.

The manufacture of MSG and other amino acid products is the business of
Ajinomoto, the company from which I source the MSG for my restaurants (through
wholesalers). Ajinomoto makes its money selling MSG and one who would act
in such a way as to disseminate anti-MSG hysteria could potentially be liable
for damages in a U.S. Civil Court. My attorney at O'Melveney and Myers
told me that this morning when I called to chat about something else, and
mentioned this issue.

My email address is located in my homenode. I invite Carol H to email
me with additional data she'd like me to put in Chinese Restaurant Syndrome
and I'll gladly put it there.

UPDATE 3/24/06:

Carol H and I have exchanged emails and she is going to give me an abstract
to place as an addendum to this writeup.

UPDATE 5/02/06:

I'm still waiting, Carol.

UPDATE 10/30/06:

I sent this message to mail@msgtruth.org
on 10/30/06:

Dear Carol:
Earlier this year you'd promised me that you would prepare an abstract of
your website and post it to www.Everything2.com under the title "Chinese
Restaurant Syndrome."
You've not done so yet. If it's a matter of difficulty coding HTML (as required
by any contributor to Everything2.com) I'd be glad to post your abstract as a
response to my writings on the subject, in the name of objectivity.
I felt awful when you said that I'd somehow maligned your website, and would
like the readers of E2 to get the whole picture. Acceptance of multiple points
of view is one of the basics of E2 that drew me to it as a forum for writers and
as a source of information in general.
I hope you're doing well.
Best regards,
Paul H. Lewis

UPDATE: Carol responded quickly with an email that explained that she'll get around to providing the requested abstract but is currently busied by her run for the Board of Selectmen in her town in, I believe, New Jersey. Who knows? If she wins, woe betide the Chinese Restaurateurs in the town — wouldn't you hazard a guess, as do I, that her first action would be to sponsor a local ordinance forbidding the vile health-threatening substance better known as MSG?